182 



STUDY OF PIG EMBRYOS. 



to the trigeminal ganglion, N. 5. The vein is cut twice, Jug' and Jug", for it 

 curves around the ganglion, passing on the inside of the ganglion between it and 



N.I i. 



Sir. 



Ven.iv. 



Me/. 



EC. 



FIG. 115. PIG, 12.0 MM. TRANSVERSE SERIES 5, SECTION 198. % 



EC, Ectoderm. F.b, Fore-brain. In/, Infundibular gland. Jug' , Jug" , Jugular vein. N.$, Trigeminal gan- 

 glion. N.7,8, Acustico-facial ganglion. N. g, Ganglion nodosum of the glossopharyngeal nerve. N.io. 

 jug, Jugular ganglion of the vagus nerve. N.n, Root of the spinal accessory nerve. Md, Medulla oblon- 

 gata. Ot, Otocyst. Str, Striae acusticte. Ven.iii, Third ventricle. Ven.iv, Fourth ventricle. X 22 diams. 



the wall of the brain. At this stage, however, it has begun to expand outward 

 behind, in front of, and below the ganglion. The expansion of the vein outward 



